1. Field of the Invention
The present invention relates to a wet sheet package offering improved sealing property and stability of quality without reducing the adhesive strength of an open/close flap due to attachment of water or oil contained in the inside liquid charged into the wet sheet package, by securely attaching, around an output opening through which to take out wet sheets on the top surface of a container for storing wet sheets, a microporous liquid-absorbent sheet exhibiting water absorbency or oil absorbency to the top surface and making this liquid-absorbent sheet and the open/close flap adherable to each other.
2. Description of the Related Art
With respect to a package for a stack of folded wet tissues or non-woven fabric sheets impregnated with cosmetic material, structures in which the output opening of the wet tissues is provided with a sheet-shaped lid coated with pressure-sensitive adhesive have been known. For example, as disclosed in Japanese Patent Laid-open No. Sho 57-022041 (Patent Literature 1) and Japanese Patent Laid-open No. Sho 58-171367 (Patent Literature 2), configurations are known wherein a cut to allow for separation (half cut area) is provided in the top surface of a pillow package and then an open/close flap coated with pressure-sensitive adhesive is adherably arranged in a manner covering the output opening after the initial opening.
In addition, when the bulk of the package decreases as the content is consumed, the area around the output opening where pressure-sensitive adhesive is coated is wrinkled and the sealing performance drops as a result. It is known that there are technologies to improve the situation as in Japanese Patent Laid-open No. 2000-229681 (Patent Literature 3) wherein a package body having a clear polyester sheet provided between a sheet-shaped lid or an open/close flap and the package material as a reinforcing plate to keep the sealing property is disclosed.
There is also a problem of reduced sealing property of the sheet-shaped lid, which is caused by wetting of the area around the output opening where pressure-sensitive sensitive adhesive is coated by water or oil in the inside liquid impregnated into the non-fabric sheets, etc. To address this problem, methods have been proposed to make this area less likely to get wet by inserting an internal frame or tray and thereby providing a buffer space, as disclosed in Japanese Utility Model Laid-open No. Sho 58-088366 (Patent Literature 4), Japanese Patent Laid-open No. Hei 01-226579 (Patent Literature 5), and Japanese Patent Laid-open No. Hei 07-41061 (Patent Literature 6).
However, the above known technologies cannot fully prevent wetting of the area around the output opening, and if the area gets wet with water or oil the adhesive strength will almost completely disappear and the sealing property will drop. As mentioned above, insertion of an internal frame, tray, etc., is effective to some extent in the prevention of this area from getting wet, but such methods cannot fully prevent the liquid contained inside from leaking out onto the area around an output opening. Furthermore, such structures would make the package bulkier and it is inconvenient for the user to carry around.
Patent Literature 1: Japanese Patent Laid-open No. Sho 57-022041
Patent Literature 2: Japanese Patent Laid-open No. Sho 58-171367
Patent Literature 3: Japanese Patent Laid-open No. 2000-229681
Patent Literature 4: Japanese Utility Model Laid-open No. Sho 58-088366
Patent Literature 5: Japanese Patent Laid-open No. Hei 01-226579
Patent Literature 6: Japanese Patent Laid-open No. Hei 07-41061